Hey Audiophil (Audiophile?)


I hope you're not in Fairfax county.

Please PLEASE tell me you're not in Fairfax county!


I am, and am also in the design stage. I figure I'll go to get permits soon.

Are the inspectors still bringing their own whips/chains?


Paul

 

Looks ok to me. I had the same thing to do in Southern NJ. It took 3 tries before I passed framing inspection. But the inspectors here were easy to deal with. They patiently showed those I am working with what needed to be done.


It would have been a lot easier if I knew what to do ahead of time. I probably should have investigated it better before starting. I would recommend anyone getting a permit to make sure they understand what the inspector is looking for ahead of time. Its worth a trip to see them if need be. It set me back about a week on a full basement project.

 

On the fireblocking - I had no issues at all. I just used 5/8" drywall to cover all gaps at the header and stuffed insulation in the gap between adjoining room. Sounds like you have an over strict county/inspector.


On the gound - the reason you need to pigtail the 2 grounds with a 3rd is so if you disconnect the recepticle the gound is still valid.


In the main I had no major issues with inspection - only problem was plumbing (easily) corrected and HVAC (once explained reson it passed).


Good luck with the rest.

 

I am framing right now, and I just can't seem to grasp where I need to fire block and where I don't. An FAQ on this would be great. I searched here and googled, but I still haven't found a resource that makes it clear enough that I can understand it. I understand the concept I think, I just am not clear where I do and don't need to put it in my room. Here is my current understanding:


Fireblocking is an attempt to prevent fire from quickly spreading from one level of a house to the next. In most places it can be 2x4's, drywall, insulation, or special caulk. It needs to block a fire that starts in a wall from spreading quickly to the next level through open air.


That's where my understanding ends. My walls and ceiling in my basement theater will be completely insulated, so do I need to do more? I still don't understand EXACTLY where I need to put it and where I don't. If someone could give a better explanation, that would be great. I've looked at some pictures, but it still hasn't clicked. So if anyone has more pictures of their fire blocking, please post.


Guy

 

In a straight forward room where all walls are stud/drywall on both side no fire-blocking required (as there is no air gap). When you start introducing concrete walls which will have gaps between the stud frame and the concrete wall you need to block that gap at the top of the wall and also to the sides to adjoining rooms. Soffits add a degree of complexity......now some jurisdictions are really strict and require every nock an cranny sealed but luckily mine just needs a reasonable blocking and not - air tight - contact your inspection office - often they have a document.

 

BritInVA is correct. Anywhere you have a vertical space going into a horizontal space, that has an air gap (no solid connection) you need to introduce fireblocking. I passed all of mine but I knew about it and how anal inspectors can be.


Although that is the 1 thing I am in total agreement with is fireblocking. Yes it is or can be a PITA but if you plan for it in the beginning (if you know about it, that is ) then it is not to bad. One thing that you can do that is easier and cheaper than alot of other methods is to use insulation. Just stuff it up in the air gaps as tight as you can get it. You may have to fold it a few times and really push it into the voids but that is one of the easiest methods to fireblock.


Another item you will have to do (at least in CO) is to put 5/8 drywall under any stairs and put one coat of tape on it - minimum.


Drew

 

If you are using clips like RSIC-1's on walls, doesn't that create an air gap between stud and drywall which would require fireblocking? Do you just insulate between the stud cavity and hat channel before drywalling? A PIA indeed.

 

Thanks for the input! OT - ok if you removed an outlet from the circuit, wouldn't you go ahead and TWIST the grounds together with a wire nut anyway? Seems crazy to wire nut two wires and then add a third to the device... Oh well, gotta be up to code...


As far as what is code for fireblocking... I was told every 10' from a doorway vertical blocking and horizontal all around the top of the wall plate to wall behind new wall. My inspector even had me caulk the cracks! I think he works for DAP or whoever made that caulk I had to buy.


Armyman... I am in the City of Manassas. Hopefully Fairfax county is less strict. I will find out tommrow if it passes...

 

From my experience in Fairfax Co. That fire code interpretation sounds pretty strict.



On the electrical for the rough-in they wanted to see all the grounds "finished"


That meant that if more than one ground wire entered a box for a given circuit the wires would be twisted together with compression fittings (easiest) or wire nuts and pigtails hanging loose for the number of grounds required.


If you used copper compression connectors you could twist two wires together leaving as many wires extending past the collar for the number of grounds needed. If there were more wires than needed you just cut them off. Pretty simple.

 

One caution about insulation...every town may not consider it adequate. In my case, after they explained what fire stop was, I asked if I could use insulation and they said no. They required sheet rock or wood and caulking around the wires.

 

when you enter the wires into the box, bond the ground wire, so you don't have to come back and do it or forget to do it.

the reason for the ground wire is to provide a path back to the panel and then to earth ground and trip the trip the breaker when their is a short to ground.

so for an example you have some equipment that shorting out against it's metal case but is current limited and doesn't trip the breaker,

that voltage is safely directed to ground, now if you break that path to ground the case and ground wire will become live.

which is why you cut the power to that circuit before touching the wiring

(and make a sign*do not turn on breaker*so the wife doesn't turn it on while you are holding the bare wires in your hand),

then you test it, then you treat the wires as if they are still live.


when making connections do so in this order,

1. ground/bonding conductor

2. neutral/identified

3. hot

and when breaking connections,

1. hot

2.neutral/identified

3.ground/bonding conductor

 

If your jurisdiction has adopted the international building code (IBC), you must provide fire blocking in wood-frame construction as follows:


1. In concealed spaces of stud walls and partitions, including furred spaces, at the ceiling and floor levels.

2. At concealed furred horizontal spaces (eg RSIC-1) at 10' intervals

3. In double wall/staggered stud walls, batts or blankets of mineral or glass fiber is allowed

4. At all interconnections between concealed vertical and horizontal spaces such as occur at soffits, drop ceilings, and cove ceilings

...some other things that don't really apply to mainstream theater builds..


Acceptable materials (except as detailed in #3): 2" nominal lumber, (2) layers of 1" lumber, one layer 3/4 plywood, 3/4 particleboard, 1/2 sheetrock, 1/4 cement board. Batts or blankets of mineral wool or glass fiber installed in such a manner as to be securely retained in place shall be permitted as an acceptible fireblock. Loose-fill insulation cannot be used unless listed for use.


Unface fiberglass batt used as fireblocking shall fill the entire cross section of the wall cavity to a min height of 16" measured vertically. When piping etc is encountered, the insulation shall be tightly packed around same.


That's about it


Tim

 

Quote:

Originally Posted by Audiophil fire blocking caulk - inspector wanted ASTM 136... that is what I used.

I can't believe he is having you go to those extremes especially with residential construction.


Mine came back a second time for the blocking, but I was able to use drywall at the back of the soffiting and mineral wool for other areas, but then my inspectors were pretty easy going. The Biotch from the Fire Department was getting way over-zealous but I had scheduled her at the same time as the City Inspectors. It worked out great b/c they talked her down from a lot of things she wanted me to do. They kept enforcing with 'Code doesn't say he has to do that...'. Great guys.

 

Quote:

Originally Posted by Neuner I can't believe he is having you go to those extremes especially with residential construction. Mine came back a second time for the blocking, but I was able to use drywall at the back of the soffiting and mineral wool for other areas, but then my inspectors were pretty easy going. The Biotch from the Fire Department was getting way over-zealous but I had scheduled her at the same time as the City Inspectors. It worked out great b/c they talked her down from a lot of things she wanted me to do. They kept enforcing with 'Code doesn't say he has to do that...'. Great guys.

Nice. I wish I had inspectors like that. My inspector didn't even show today... no call, nada. I went to work in the afternoon/evening and on the way stopped by city hall.


Their response was they got "busy" and would try again "sometime" tommrow. Also, if I do not pass this inspection I have to pay $100 ($50 each trade) fine. So, another day of lost productivity for me I guess... Never again will I pull a building permit! Anyone building anything in the City of Manassas, VA..... unless you are removing a load bearing wall/breaker panel/something equally dangerous, don't bother, they are major hassle!


-Audiophil

 

As a follow up and more fireblocking info... my inspections passed today, the inspector was just looking for something wrong... he noticed a small gap in my fireblocking, but luckly I was ready with a new tube of fire caulk and he let me fill it and it passed... very strict.


On the topic of fireblocking material, the inspector stated, you could not use insulation as the fireblocking material unless it was some special rock wool type, then it would be ok. As we can see from this thread, codes vary quite a bit across the country. Also, any pipe entering a wall must be sealed as well. Inspectors are a wealth of knowledge, eh?

 

You know what they say "Those that can - Do, Those that can't - Teach (or Inspect)"


Glad you passed

 

Audiophil:


Glad to hear you passed.

Quote:

On the topic of fireblocking material, the inspector stated, you could not use insulation as the fireblocking material unless it was some special rock wool type

Sometimes it also has to be crushed/fixed (with for example a length or two of angle iron and bolts to provide compression) so that an explosion won't move it (as opposed to simply filling the cavity as Mr.Tim described in his excellent post above). I've seen a little vertial wall of foil backed rockwool, fastened top and bottom, that was a firestop.

Quote:

Also, any pipe entering a wall must be sealed as well.

I've definately heard of that one. I remember a Discovery Channel show with firefighters going through a commercial structure and opening up walls and ceilings and finding changes that had been done in the past 10 years without inspections, and one of the things they kept finding was new pipes going through concrete walls up above false ceiling level without firestopping around them. The word is 'penetrations'.


Quote:

(from Fairfax County Virginia "Based on the 2000 Virginia Uniform Statewide Building Code") FIRE BLOCKING: Fire blocking shall be provided to cut off all concealed draft openings and to form an effective fire barrier between stories. Fire blocking shall be provided in the following locations. • In concealed spaces of stud walls and partitions, including furred spaces, at the ceiling and floor level and at 10'-0" intervals; • At all interconnections between concealed vertical and horizontal spaces such as occur at soffits, drop ceilings, cove ceilings, etc; • In concealed spaces between stair stringers at the top and bottom of the run. • At gaps 1" or less and at openings around vents, pipes, and ducts at the ceiling and floor level; batts or blankets of mineral wood or fiberglass must be used. FIRE BLOCKING MATERIAL: Fire blocking shall consist of one of the materials listed below. The integrity of all fire blocking must be maintained. • 2x lumber (2x4, 2x6, etc.). • Two thicknesses of 1x lumber (1x4, 1x6, etc.) with staggered joints. • One thickness of 23/32" of plywood or OSB with joints backed with the same material. • One thickness of 3/4" particleboard with joints backed same material. • 1/2" gypsum board • 3" cement based millboard. • Batts or blankets of mineral wood or fiberglass. INTERIOR COVERING: Wall and ceiling material must meet the requirements below. • Materials must have a flame spread classification no greater than 200 and a smoke density classification no greater than 450. This does not apply to trim, molding, handrails and doors. • Water resistant drywall must be installed on walls of bathtub and shower spaces and finished with a non-absorbent surface. • Wood veneer or hardboard paneling less than 1/4" shall not be permitted.

Quote:

My inspector didn't even show today... no call, nada

Have you watched the movie "The Money Pit" (Tom Hanks, Shelly Long)?